}
+void CursorSlice::forwardPos()
+{
+ // move on one position if possible
+ if (pos() < lastpos()) {
+ //lyxerr << "... next pos" << endl;
+ ++pos();
+ return;
+ }
+
+ // otherwise move on one paragraph if possible
+ if (pit() < lastpit()) {
+ //lyxerr << "... next par" << endl;
+ ++pit();
+ pos() = 0;
+ return;
+ }
+
+ // otherwise try to move on one cell if possible
+ if (idx() < lastidx()) {
+ //lyxerr << "... next idx" << endl;
+ ++idx();
+ pit() = 0;
+ pos() = 0;
+ return;
+ }
+ BOOST_ASSERT(false);
+}
+
+
+void CursorSlice::backwardPos()
+{
+ if (pos() != 0) {
+ --pos();
+ return;
+ }
+
+ if (pit() != 0) {
+ --pit();
+ pos() = lastpos();
+ return;
+ }
+
+ if (idx() != 0) {
+ --idx();
+ pit() = lastpit();
+ pos() = lastpos();
+ return;
+ }
+
+ BOOST_ASSERT(false);
+}
+
+
+bool CursorSlice::at_end() const
+{
+ return idx() == lastidx() && pit() == lastpit() && pos() == lastpos();
+}
+
+
+bool CursorSlice::at_begin() const
+{
+ return idx() == 0 && pit() == 0 && pos() == 0;
+}
+
+
bool operator==(CursorSlice const & p, CursorSlice const & q)
{
return &p.inset() == &q.inset()